Unique partnership brings new cancer treatment to life

IsoRay's brachytherapy seeds use cesium-131, which emits a low-energy x-ray that effectively provides a cancer-killing dose to a tumor in a short period of time.

IsoRay is a company that started as a good idea and, in less than a decade, has grown into a publicly traded corporation. "IsoRay literally started in Lane Bray's basement, with about three employees," said Larry Greenwood, the Pacific Northwest National Laboratory technical lead for the IsoRay project.
IsoRay Medical, Inc., produces cesium-131 radiochemical brachytherapy "seeds" used to treat prostate and other cancers. The cesium-131 seed offers a significantly shorter half-life than the two other isotopes commonly used for brachytherapy. A shorter half-life means faster delivery of therapeutic radiation to the prostate gland and lower probability of cancer cell survival.
IsoRay's partnership with PNNL began almost as informally as the company did. In 1998, Bray, a PNNL retiree and internationally recognized expert in medical isotopes, and Don Segna, a retired engineer formerly with the U.S. Department of Energy, met with Larry Greenwood to discuss technical issues related to the fledgling company. This meeting led IsoRay to PNNL's Economic Development Office and access to PNNL expertise in the form of a Laboratory Technnology Assistance Program project.
Five additional TAP projects, several research contracts, and seven years later, IsoRay was producing and marketing its cesium-131 seeds to hospitals across the nation.
As a small start-up company, IsoRay did not have the physical or financial resources to conduct extensive testing in a radioactive environment. The company began by performing nonradioactive testing in a technology incubator facility before conducting the radioactive work at PNNL.

"It would have been nearly impossible to start this company without a laboratory like PNNL available to us," said Don Segna, now IsoRay's vice president of strategic planning. "The advantage of having a place like PNNL where we could do the radioactive work at a relatively low price meant that we didn't have to go public right away. We could still determine the company's direction."

In addition to providing a radiological lab and expertise, PNNL offered its regulatory experience. "We are used to the oversight involved in working with radioactive materials so we know the ins and outs of quality control and the documentation needed to make it happen," Greenwood said. "We also have DOE support for our work with small companies."

"We got our feet wet at PNNL, learned what kind of equipment we needed and how the regulatory process worked," said Bray, who is now chief scientist at IsoRay. "We still rely on Larry's group for analytical services and look forward to working with them in the future."

IsoRay's cesium-131 seeds are now being used in 36 medical centers and clinics around the United States. The cesium-131 seed has a half-life of 9.7 days, compared to 60 days for iodine-125 seeds and 17 days for palladium-103 seeds. Because of this shorter half-life, it delivers more than 90 percent of its total radiation dose in less than 33 days, attacking the cancer faster and reducing the incidence of common brachytherapy side effects.

"We now have a product that appears as if it could become the seed of choice for the treatment of prostate cancer," Segna said. "We've had some requests for using the cesium-131 for treating other cancers and are exploring those possibilities."

IsoRay developed all of the intellectual property and holds all of the patents for the separation and purification of cesium-131. IsoRay recently built its own radiological laboratory in Richland, Washington, and is now producing the seeds there. The cesium-131 seeds won a Federal Laboratory Consortium award in 2006 for the transfer of technology from a national laboratory to the public.

"Staff here really love working on the project, and we have great interaction with the IsoRay people," Greenwood said. "We also get a great deal of satisfaction from being involved with a project that may save someone's life."

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IsoRay is based in Richland, Washington. More information about IsoRay is available at www.isoray.com.

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